1. Field of the Invention
This present invention relates generally to control systems, and more particularly to a delay coordinating system for controlling a plurality of agricultural products (crop input) release points on an agricultural machine in response to various inherent delay times between predetermined vehicular mounted control points and the ultimate machine crop input dispensing points. The time variance of each different dispensing point and release point must be measured and all the varying times coordinated by a computer program to bring them all together at the precise moment in time for the desired dispensing moment.
2. Description of the Prior Art
Various agricultural product applicator systems and associated methods of control have been suggested at one time or another, but in each instance, these systems leave something to be desired. For example, there is a need for an applicator system that ensures agricultural products dispensed from a moving applicator machine are accurately and precisely combined prior to being dispensed. Agricultural product applicator systems which estimate an average composite dispensing delay time experienced when dispensing crop inputs from a moving product applicator machine have been developed. Generally, these systems are limited to use of a cursor on a display device to locate a field reference point in front of a moving machine and then apply an estimated or average product dispensing delay time such that conveyance or flow of any/all product(s) to be dispensed at the field reference point will be initiated at a single common predetermined moment before the machine reaches the target point. The point at which product flow is initiated is determined from factors including ground speed of the applicator machine and the total amount of time it takes from the moment when crop input flow is initiated from onboard the machine and the moment a crop input is dispensed from a wet boom, dry boom, and/or injector tube, for example. However, the variable nature of flows and random locations of various crop input release points associated with multiple storage devices create unaccounted for delays and result in misapplications and inaccurate combinations of multiple crop inputs.
One system known to those skilled in the art of agricultural products (crop input) application includes an agricultural machine having a single bin containing planting products such as seeds or crop input application products such as herbicides, insecticides, fertilizer, anhydrous ammonia, various chemicals, or other crop input products. Generally, such systems are ground-speed coordinated to start metering crop inputs from the product bin when the applicator machine reaches the target point, generally ignoring the lag or delay time between the start of product release from the product bin and the time a desired product reaches the ground.
Still needed, but not available with product applicator machines and associated control systems presently known in the art is an agricultural products crop input applicator system which allows a product applicator machine to commence and terminate metering a plurality of planting or crop input products at different moments in time for a common reference point in a field, for example. Such a need exists for product applicator machines having multi-product storage devices such as bins mounted upon the machine or having multi-conveyor and/or product flow devices or having multi-point product dispensing devices, for example. It can readily be appreciated that use of a single estimated or average composite system delay will be inadequate to provide for accurate and precise application of multiple agricultural products when variable rate applications are being made, i.e. where more than a single product, storage device, e.g. bin, or material transport system, i.e. conveyor is used with the machine.
A solution is to provide a variable rate, multiple crop input applicator machine with a time delay coordinating system which is capable of taking into consideration the nature of the individual products to be dispensed, the location of the individual product storage devices, i.e. bins, boxes, tanks, etc., and the type and nature of each dispensing device employed, wet booms, dry booms, nozzles, conveyors, spinners, planters, drop tubes, injectors, etc., as well as the ground speed when variable rate applications are made across a field. Such a coordinating system must be capable of evaluating each system feature such as stated above and coordinating a unique delay time for each agricultural product (crop input) dispensed from the applicator machine. Using such a system will then prevent premature or latent application of the agricultural products (crop inputs) to a desired target area traversed by the applicator machine. Unless the timing delay differences associated with the various machine release points are considered and coordinated, accurate and precise applications are impossible. The present invention provides a solution for the management and control of the aforesaid differences.
Modern applicator machine control systems typically have a host controller located within the operator cab of the machine, including a processor with associated input and output devices. The host is generally directly linked to at least one other controller which may also be located within the cab, and which is responsible for all communication to devices on the machine, such as shown in U.S. Pat. No. 4,630,773, issued Dec. 23, 1986, to Ortlip, entitled Method and Apparatus for Spreading Fertilizer, and U.S. Pat. No. Re 35, 100, issued Nov. 28, 1995, to Monson et al., entitled Variable Rate Application System, both assigned to Ag-Chem Equipment Company, Inc. of Minnetonka, Minn., the Assignee of the present invention. The system disclosed in the '100 reissue patent comprises a controller accessing a soil map indicating a soil characteristic for each portion of the field. Field locations and status maps indicating current crop input level at various locations in a field to be treated are monitored by a control system. A crop input map is updated after a dispensing pass to provide a real-time record. Position locators for the machine in the field may include "Dead Reckoning", GPS, or LORAN systems, for example.
Similarly, U.S. Pat. No. 5,355,815 discloses a closed-loop variable rate applicator. The system operates by determining a soil prescription in near real-time and dispenses crop inputs to the soil scene as a fraction of the soil prescription. The '815 patent is also assigned to Ag-Chem Equipment Company, Inc. and is incorporated herein by reference in its entirety.
Another system is disclosed in U.S. Pat. No. 5,453,924, issued Sep. 26, 1995, to Monson et al., entitled Mobile Control System Responsive To Land Area Maps. This system expands on earlier known applicator machine controls systems including those assigned to Ag-Chem Equipment Company, Inc., by incorporating a network scheme which links a host controller positioned within the operator cab to multiple controllers located at various points on the machine external to the operator cab. All of the above patents are assigned to the Assignee of the present invention and are incorporated by reference in their entirety herein. The control systems discussed herein above describe systems which, when properly adapted with the inventive algorithmic software and associated control devices, may be used to practice the present invention.